Method of combatting fungi with 2-thiocyano-4, 6-bisalkyl amino-2-triazines



United States Patent 3,120,468 METHGD UH COMBAT'IING FUNGI WITH Z-THIO- CYANO- LG-BBALKYL AMHNO-S-TRIAZINES Werner Schwarze, Frankfurt am Main, Germany, assignor to Deutsche Goldand Siiber-Seheideanstalt vormals Roessler, Frankfurt am Main, Germany No Drawing. Filed Aug. 22, 1962, Ser. No. 218,576 Claims priority, application Great Britain May 17, 1961 6 Claims. (Cl. 16733) The present invention relates to novel amino derivatives of thiocyano triazine having fungicidal properties of the general formulae and N N R (I) r R wherein (SCN) represents the Rhodano radical SCEN or the isothiocyanate radical N=C S, R is selected from the group consisting of lower alkyl, chloro lower alkyl, cyano lower alkyl, phenyl, ethoxy phenyl, and chloro phenyl and R is selected from the group consisting of hydrogen, lower alkyl, chloro lower alkyl, cyano lower alkyl, phenyl, ethoxy phenyl and chloro phenyl and a method of combatting fungi therewith.

Preferably the compounds according to the invention are the mono thiocyano diamino triazines in which the amino groups are substituted by lower alkyl groups, the total number of carbon atoms of which is 4 to 8, and particularly those in which one of the amino groups is an ethyl amino group as these compounds combine especially high fungicidal activity with low phytotoxicity. The following are illustrative of such preferred compounds:

2-thiocyano-4-ethyl amino-fi-dimethyl amino-s-triazine 2-thiocyano-4-ethyl arnino-6-diethy-l amino-striazine 2-th-iocy'ano-4-ethyl amino-6-isopropyl amino-s-triazine 2-.thiocyano-4-ethyl amino-6-sec. butyl am-ino-s-triaaine 2-thiocyano-4-ethyl amino-6-isobutyl arnino-s-triazine 2-thiocyano-4-Inethyl amino-6-diethyl amino-s-triazine 2-thiocyano-4-dirnethyl amino-6-dimethyl amino-s-triazine 2-thiocyano-4-isopropyl amino-6-isopropyl amino s triazine 2-thiocyrano-4-isopropyl amino-6-tert. butyl amino-s-tria- Zine 2-thiocyano-4-n-butyl amino-6-dibutyl amino-s-triazine The novel -s-triazine compounds can easily be prepared by reacting an alkali metal or alkaline earth metal or ammonium thiocyanate with triazine compounds of the a; 3,120,468 Ce Patented Feb. 4, 19

formulae Hal-O (If-Hal R1-N R(IJ (Ii-Hal N N N N t r N R ITIR R1 R1 in which R and R have the same significance as above and Hal denotes halogen, preferably chlorine or bromine, in the presence of a lower alkanol, preferably methanol, as a solvent. The reaction can be carried out at any temperature between the freezing point and the boiling point of the mixture. The reaction takes place smoothly even at temperatures as low as -40 C. However, in order to accelerate the reaction it often is advantageous to use elevated temperatures.

The novel compounds according to the invention can be produced by still another method, namely, by reacting s-tr-iazine derivatives of the formulae with a cyanogen halide, such as cyanogen chloride or bromide, in the presence of a solvent, such as water, lower alkanols, for example, methanol, ethanol, and ketones, for example, acetone, and methyl ethyl ketones. The reaction with the cyanogen halide is advantageously carried out in the presence of a hydrogen halide acceptor at temperatures below room temperature to prevent any reaction of the cyanogen halide land the solvent. Preferably, temperatures between about 5 C. and +10 C. are employed.

The compounds according to the invention possess excellent fungicidal properties and therefore are useful as fungicides. For examples, in spore tests carried out on wall flower (Cheiranthes cheiri) leaves infected with spores of Alternaria brassz'ciola employing dispersions of the compounds in water, it was found that the compounds, for example, cyan-methyl-amino dithiocyano triazine, beta-chloro-ethyl-amino d-ithiocyano triazine and bis-isopropylamino thiocyano triazine, provided effective control at concentrations below 5000 p.p.m.

Also, in tests against the fungus Alternaria tenuz's the following results were obtained:

LD Period Compound amount, observed,

7 per 0111 hours p-Ohlor0-anilido-di-thiocyano triazine 2O 20 o-Chloro-anilidodithiocyano triazine 0. 4-0. 8' 20 3 sions, which were stabilized by addition of polyglycol ethers.

Powdery mildew infection The claimed compounds can be used as fungicides in the form of solutions, suspensions, dispersions and on solid carriers.

The following examples will serve to illustrate several embodiments of the invention.

Example 1 275 g. of dichloro-o-chloro anilido triazine were boiled with a solution of 200 g. of potassium thiocyanate in 2.4 liters of methanol for two hours under reflux. The reaction mixture was then cooled and the precipitated KCl filtered ofi. The filtrate was concentrated under vacuum to 750 cc. and cooled. The crystals formed were vacuum filtered and washed with methanol and water and recrystallized from methanol. Yield 198 g. of 2.4 di(SCN)- 6-o-chlor0 anilido-s-tr-iazine of a MP. of 122-123 C. The yield therefore was 61.7% of the theoretical.

Example 2 275 g. of dichloro-p-chloro-anilido triazine were heated with 160 g. of ammonium thiocyanate in 2 liters of methanol as described in Example 1. Yield 183 g. 2.4 di(SCN)-6-p-chloro-anilido-s-triazine of a M. P. of 192 C. The yield therefore was 57.1% of the theoretical.

Example 3 28.5 g. of dichloro-phenetidino-triazine were introduced in a solution of 20 g. potassium thiocyanate in 400 cc. of methanol and the mixture boiled for 2 hours under reflux. Yield 15.6 g. (47.3% of the theoretical) of 2.4 di(SCN)- 6-pl1enetidino-s-triazine of a M.P. of 162 C.

Example 4 54 g. of o-chloro-aniiino-dimercaptotriazine were dissolved in 500 ml. of 0.8 N sodium hydroxide. The solution was cooled to C. and 30 g. of cyanogen chloride were gradually added thereafter. During the reaction the temperature climbed to +10 C. After a total elapsed time of 30 minutes the resulting precipitate was filtered off on a suction filter and Washed Well with water. The precipitate which was then dried under vacuum, amounted to 62 g. of analytically pure o-chloro-anilino-dithiocyanotriazine which had a melting point of 130 C. The yield was 96.8% of the theoretical.

Example 5 5.4 g. of p-chloro-anilino-dimercaptotriazine were dissolved in 200 ml. of 0.2 N sodium hydroxide. This solution was cooled to 0 C. and a solution of 5 g. of cyanogen bromide in 50 ml. of acetone was added to it dropwise. At this point the temperature was +2 C. The solution was stirred continuously for one hour. The resulting precipitate, p-chloro-anilino-dithiocyanotriazine was filtered off on a suction filter and dried. Its melting point was 192 C. The yield, 5.5 g., corresponded to 86% of the theoretical.

Other compounds which were produced in an analogous manner are:

fi-chloroethyl-amino dithiocyano triazine Cyan'methyl-amino dithiocyano triazine Bisisopropyl-amino thiocyano triazine Bisbutyl-amino thiocyano triazine Bisethyl-amino-thiocyano triazine Bismethyl-amino thiocyano triazine Bisdimethyl-amino thiocyano triazine CycloheXyl-amino dithiocyano triazine Diphenyl-amino dithiocyano triazine Ethyl-amino dithiocyano triazine Methyl-amino dithiocyano triazine Ethyl-amino isopropyl-amino thiocyano triazine Ethyl-amino butyl-amino thiocyano triazine Ethyl-amino dimethyl-amino thiocyano triazine Ethyl-amino diethyl-amino thiocyano triazine Methyl-amino diethyl-aminothiocyano triazine Diisopropyl-amino thiocyano triazine Isopropyl-arnino t.butyl-amino thiocyano triazine N-butyl-amino diethyl-amino thiocyano triazine Example 6 388 g. of 2-ethyl-amino-4-tert. butyl-amino-6-mercaptotriazine were dissolved in 1710 ml. of n-sodium hydroxide. The solution Was cooled at -5 C. The solution was stirred and 100 ml. of liquid cyanogen chloride were added. After 10 minutes the mixture becomes alkaline and it results in a precipitate of 2-ethyl-amino-4-tert. butylamino-6-thiocyano triazine. The precipitate was filtered off, washed with water and dried, then recrystallized from a mixture of benzene and white spirit. Its melting point was to 91 C., the yield 411 g. corresponding to 95.4% of the theoretical.

Example 7 15 g. of 2-dimethyl-amino-4-isopropyl-amino-6-mercapto-triazine were dissolved in 71 ml. of n-sodium hydroxide. The solution was cooled to -5 C. and mixed with 5.3 g. of liquid cyanogen chloride. The precipitate was treated as described in Example 6. Obtained were 16.6 g. of Z-dimethyl-amino-4-isopropyl-amino-6-thiocyano-triazine in the form of colorless crystals with a melting point of 117 to 118 C.

This application is a continuation-in-part of applications Serial No. 189,324, filed April 23, 1962, and Serial No. 33,649, filed June 3, 1960, which in turn is a continuation in part of applications Serial No. 719,997, filed March 10, 1958, now abandoned, and Serial No. 827,722, filed July 17, 1959, now Patent No. 2,996,505.

I claim:

1. A method of inhibiting the growth of fungi which comprises applying to the habitat an effective amount of a triazine compound of the formula wherein R is lower alkyl and R is selected from the group consisting of hydrogen and lower alkyl, the total number of the carbon atoms in the alkyl groups of such groups being between 4 and 8.

2. A method of inhibiting the growth of fungi which comprises applying to the habitat an effective amount of a triazine compound of the formula wherein R is lower alkyl and the total number of carbon atoms in the R groups and the C H group is between 4 and 8.

4. A method inhibiting the growth of fungi which comprises applying to the habitat of the fungi an effective amount of Z-thiocyano-4,6-bisisopropyl-aunino-s-triazine.

5. A method inhibiting the growth of fungi which comprises app-lying to the habitat of the fungi an elfective amount of 2-thiocyano-4-ethyl-6-tertiary butyl-amino-striazine.

6. A method inhibiting the growth of fungi which comprises applying to the habitat of the fungi an effective amount of 2-thiocyano-4-ethyl-6-diethyI-amino-s-triazine.

References Cited in the file of this patent UNITED STATES PATENTS 2,368,451 DAlelio Ian. 1945 2,650,220 Roemer et a1 Aug. 25, 1953 2,720,480 Wolf Oct. 11, 1955 2,864,820 Sheers Dec. 16, 1958 2,907,763 Hosler Oct. 6, 1959 2,959,519 Speziale et a1 Nov. 8, 1960 2,996,505 Schwarze Aug. 15, 1961 FOREIGN PATENTS 338,643 Sweden July 15, 1959 1,263,177 France Apr. 24, 1961 

1. A METHOD OF INHIBITING THE GROWTH OF FUNGI WHICH COMPRISES APPLYING TO THE HAVITAT AN EFFECTIVE AMOUNT OF A TRIAZINE COMPOUND OF THE FORMULA 